This invention relates to a method and apparatus for delivering fluids from a disposable container with flow control to avoid spillage.
Fluid delivery systems have been in use since ancient times. It was not uncommon for cities of old to arrange a water reservoir some distance from the city, for example, in nearby foothills, and to convey the water for use in the city via aqueducts, to the points of consumption, by gravity.
Today, in many applications, the basic principles of long ago are still in use. For example, household and industrial water is often stored in reservoirs, often referred to as xe2x80x9cheadxe2x80x9d tanks positioned above the points of application, being piped to a point of delivery under gravity, with the flow being controlled by valves, taps or faucets.
In more modestly sized applications, such as in industrial fluid delivery systems, specialized fluid delivery systems are commonly employed to provide delivery of a variety of fluids in addition to water, such as oils, chemicals, and the like.
There are also relatively small fluid delivery systems, such as used in restaurants or in catering, for delivering small quantities of fluids such as used to dispense condiments such as ketchup, though gravity delivery of more viscous materials is often unsuccessful with gravity alone. Most often such fluid dispensers rely on various pumps for dispensing these products in small dosage amounts.
In such applications, the fluid reservoirs may be made of flexible impermeable sheeting or polymer film, which can be shaped into a bag-like or bladder-like structure. Such a flexible bag or bladder can take a convenient shape permitted by its surroundings, without detrimentally affecting its fluid retaining capacity. Generally, for safe transport without puncturing or tearing flexible container, the container is typically placed in a suitable housing, such as for example, a cardboard carton, and the like. A typical example would be an inexpensive wine container, where wine is delivered in a bladder in a cardboard carton, with an on/off valve for dispensing the wine to smaller containers or glasses.
Flexible reservoirs or containers possess some significant advantages over rigid types. For example, a water-filled pouch constructed out of a flexible sheet polymer is resistant to some extent to damage. For example, such a pouch is unlikely to rupture on falling from a typical worktop or get counter height, whereas a rigid container made of glass, rigid plastic and even metal, may fail on impact. Also, the flow from a rigid container can be disrupted if adequate provision is not made to allow air to enter into the container to replace void volume created by the dispensed fluid. In such a case, for example where the air intake becomes blocked, the flow will simply stop. A flexible container needs no such make-up air. Being flexible, the container simply contracts in correspondence to the volume of fluid dispensed. Flexible containers are also usually lighter and less expensive than their rigid counterparts, and provide better recycling opportunities.
There are however some disadvantages to the use of flexible containers. One difficulty which has limited the use of such containers is that too often, upon making an opening in a flexible container, the act of handling necessary to set-up or dispense fluids causes uncontrolled ejection of at least a portion of the fluid contents. Attempts have been made to address this problem, with varying degrees of success. In one attempt, a sealing film is placed over a fluid dispensing duct having a dispensing aperture. In use, the sealing film is pierced by insertion of a piercing plug into the aperture. This type of connection is typically used in for intravenous infusion of liquids and medicament, also known as IV or drip bags. Unfortunately, in such a case, the aperture cannot be resealed and remains open after use.
The incorporation of a manually operated control valve in place of the pierceable film provides better fluid control. One example as discussed previously is found in the xe2x80x9cboxedxe2x80x9d wine form of packaging, where a dispensing on/off valve is used. While this form of control under direct manual operation is adaptable to certain applications, it cannot be used in more complex delivery systems, for example where the fluid is dispensed intermittently over time and it would be impractical for someone to simply stand by the valve to dispense liquid on command. There is also the disadvantage which exists with any manually operated shut off system, which is that the valve can be left open through inattention, or be inadvertently opened, releasing the fluid.
An IV type of flexible container is usually has a length of narrow bore tubing, having a valve arrangement suitable for attachment to such fluid conduits. The tubing facilitates dispensing the fluid at its distal end. With such an arrangement, the risk of spillage is greatest at the conclusion of the fluid delivery procedure. Any residual fluid may be released when the tubing is disconnected from the flexible container.
This problem is exacerbated when flow monitoring and/or additional control valves are included in-line with the fluid conduit at the distal point, since it can be erroneously assumed that since the flow has stopped, the flexible container is empty
It is an object of the present invention to provide a fluid dispensing system which overcomes the disadvantages of the prior art.
It is another object to provide a fluid delivery system which can uses a flexible container, yet which allows for unsupervised fluid dispensing.
It is another object to provide a fluid delivery system which reduces or eliminates spillage when disconnecting a delivery tube from the fluid container.
These and other objects of the present invention are achieved by a system for filling a container comprising a flexible bag containing a dispensable material therein, the bag having a dispensing opening having means for communicating with a dispensing conduit, a dispensing coupling for removable placement in the receiving means and connected to the dispensing conduit, and a flow regulator for regulating material flow from the flexible bag to the container through the dispensing conduit to the container.
Preferably, the receiving means is a socket, the dispensing opening having a push type of valve for preventing fluid flow during transport and storage of the bag. The dispensing coupling is then first received by the socket, to form a seal, further insertion of the coupling engaging the push valve to initiate fluid flow.
Using the present invention, virtual leak-free dispensing of fluids is achieved and discontinuance as well can be undertaken with a limited loss of fluid as the push valve is closed prior to the coupling leaving the socket.